Dry filter



my wm www@ E. S. HARRISON DRY FILTER July 8 E940 3500328 B. s. HARRISON DRY FILTER ed March $1 5 Sheets-Ehe Will li Judy 8 E924 I E. S. HARRISONl DRY FILTER Filed March, 51, 1922 5 Sheets-Sheet July 8 1924.

B. s. HARRISON' DRY FILTER Filed March 31, 1922 5 Sheets-Sheeft 5- azgy.

Inl/@MOT Patented July 8, 1924.

STATES PATENT `oFl`=1c|aA BURT S. HARRISON, OF CHICAGO', ILLINOIS, ASSIGNOR TO DRYING SYSTEMS, INC., OF

' CHICAGO, ILLINOIS, A. CORPORATION 0F ILLINOIS. v

DRY FILTER.

Application led March 31, 1922. SerialNo. 548,379.

To all whom it may concern.:

Beit known that I, BURT S. HARRISON,

a citizen of the United States .of America,

and a resident of Chicago, county of Cook,

and State of Illinois, have invented a new and useful Improvement in Dry Filters, of which the following is a specification.

This invention relates to dry fabric filters of the general class employing zigzag ar- .10 rangementsof filtering cloth or screens. It

Ais customary to stretch the cloth on' frames,

and vthe object of the present invention is to overcome the disadvantages resulting from the use of frames. It is comparativel slow and tedious work in case of a filter o large capacity to take out the frames and clean the cloth, and it is frequently ydiiiicult to replace the frames in a manner to` avoid leaving air leaks around the same. For this and otherv reasons the cleaning or replacement of the cloth lis often neglected when it should be done. If the cloth is not replaced when the interstices thereof become seriously filled with material, there is a reduction in the 25. flow of air, or else when used in connection These objections tothe frame type of-filter` are overcome by the constructionillustrated in the accompanying drawings, in which-` Figu tion along the line l-l of Fig. 2.

Fig. 2 is a transverse vertical section taken on the line 2 2 of Figure 1.

Fig. 3 is an enlarged detail in side lelevation illustrating the manner in which the lter cloth is supported.

cloth and supports therefor.

Fig. 5 is a fragmentary plan view of the re 1 is a -side elevation of part of. the filter, but with the casing shown sec` Fig. 4 is an enlarged longitudinal section Y illustrating the arrangement of the lter livltergcloth and its supports as illustrated in -Fig. 6 is another plan view similar toFig. 5, but showing some of the adjusting brack- 'ets for the upper cloth supporting rods in section.

Fig. 7 is a sectional detail taken on the line 7-7 of Fig. 3.

Fig. 8 is a sectional detail taken on the line 8-8 of Fig. 3.

Fig. 9 is an end view with .the casing in section illustrating va multiple stage arrangement of filters of the type illustrated by the remaining drawings.

It is customary in filters of this general class to use cloth cut to -definite dimensions to lit corresponding wood frames to which the cloth is fastened by tacks and these frames are slid into a casing having cleats at the top and bottom for guides, the frames being arranged in zigzag relation. In the present arrangement a bolt of cloth is placed in the apparatus in one piece, which is looped vertically in festoons or zigzags, the tpV of each loop passing over a tube, and

the bottom of each loop passing under a tube. Y,

The side casing or lter backs are serrated to correspond with the cloth festoons, and the edges of the serrated casing are Hanged outwardly at ninety degree (90), and over which edges the edges of the cloth are folded and secured by means of metal clips which extend the length of each of the loops or festoons.- The supporting tubes for the cloth festoons are removably mounted in brackets at the sides of the casing, and in order to install the filtering cloth in the casing the upper tubes are first laid on the floor between and beneath the lower supportingtubes which remain in their brackets. One end of the cloth is then secured by a clipl to flange 17 and the bolt is then rolled out over the tubes which lie on the floor, and then these tubes are sucessivelylifted at their ends and placed in the upper supporting brackets, thus bringing the cloth into the festoon arrangement as illustrated. The cloth is then cut and secured at the cut end, and is finally tightened to the desired `degree by means of adjusting screws on the upper brackets.

The saving of timeei'ected by this design results from the arrangement not requiring that the cloth be cut into' a plurality of pieces for fitting frames; that the holding removal of wooden frames and taking out the tacks as is required with filters of this general class, and now in use.

Referring to the drawings, the casing 1 1s formed to provide an incoming air conduit 2, and an outgoing conduit or air box 3, the latter having downwardly projecting serrated sides 4: The incoming air conduit 2 is divided from the air box 3 by the festoons of filter'cloth 5 which follow the 'form of' the serrated sides 4 of air box 3. The air to be filtered, therefore, travels as indicated by the arrows 6 in Fig. 1, upwardly into the spaces 7 formed by the festooned filtering cloth and then through the clot-h into the outlet box 3.

The tubes 8 at the bottom of the filter, and the tubes 9 at the top and around which the cloth is looped, rest in hangers 10 supported .by the knife-edge lugs 11 on bracket-s 12 secured to the casing as illustrated in Fig. 8. Threaded into the lower ends of the .hangers 10 are winged screws 13 by means of which` the tubes 8 and 9 are clamped to the lugs 11. The serrated depending side portions 4 ofthe air box casing have their edges flan ed out at. ninety degrees (90) and doub ed over as illustrated in Fig. 7. Metal clips 14 are sprung. over the doubled-back edges 15 of the serrated sides 4 in order to securely Vfasten the said edges of the cloth. The ends of the cloth are similarly lfastened to the end walls 16 of the outlet box 3 at the bent lower edge 17 of these end walls, Fig. 4.

To install the filtering cloth in the structure, the lower row of tubes 8 areA first clamped in position inthe hangers at the bottom of the serrated sides of the air box,

the thumb screws being tightened up to clamp the tubes firmly in place. The tubes which are to be supported at the top of the structure are laid on the floor between the tubes of the lower row. The end of the bolt of filtering cloth is then passed over the first tube 9 of the upper row, which l.tube may be clamped in its final position, and the cloth is secured by a clip to the bent end 17, Fig. 4, of the end wall 16 of outlet box 3. The bolt is then rolled out beneath the lower row of tubes 8. Then the upper row of tubes are one after the other lifted and placed into their supporting brackets, leaving the filtering cloth in the desired festooned arrangement, the cloth passing over,

the upper tubes and under the lower tubes throug out the length of the filter. The cloth 1s then fastened by a clip at its opposite end asillustrated in Fig. 4, and the winged screws 13 for the upper tubes are then tightened, which serves to slightly raise the tube and stretch the cloth while firmly fastening the tubes in place.

The side edges of the cloth now extend slightly beyond both of the serrated side n plates of the outlet box 3, the total width of l the air box being slightly less than that of the cloth to be used. These edges are now folded over the flanges 15, Fig. 7, of the serrated sides of the outlet box 3 and secured means of clips 15.

The filter may, of course, be operated by a fan pressure on the filter forcing the air through the filter and out through the air box 3, or it may be operated by fan suction, pulling the air through the outlet box.

Figure 9 illustrates a plurality of such filters in superimposed relation so that the air may travel upwardly and successively through the different filters. By causing the air to travel upwardly through the lter some of the material carried therebyl may settle back to the Hoor by gravity without striking thecloth. This figure shows air inlets 18 at the bottom, and an outlet 19 at the top, and between these `inlets and outlet a plurality of the filters 20 such as above described, supported in a housing 21, floors 22 being arranged between the different/filters. A

scribed it will be understood that numerous details of the construction shown may be altered or omitted without departing from the spirit of this invention as defined by the following claims.

I claim z' 1. A filter of the class described comprising a housing having an inlet and an outlet, longitudinal depending serrated partitions in said housin a double row of supporting bars' extending between said partitions part at the bottom and part at the top of the serrations, a filtering cloth stretched vin festoons between said bars, and metallic clips substantially U-shaped in cross section for securing the filtering cloth to the edges of said serrated partitions.

2. A filter of the class described comprising a housing having an inlet and an outlet,V longitudinal depending serrated partitions in said housing, a row of supporting bars extending between said partitions at the bottom and another row at the top of the serrations, and a filtering cloth stretched in festoons between said bars, said serrated partitions having fianges bent outwardly from their edges, and spring clip means for securing the edges of the filtering cloth to said flanges, said means being adapted to be easily sprung into place manually.

3. A filter of the class described comprising a housing divided into two parts by a festoon of filtering cloth, two rows of bars supported in said housing and between which the iltering cloth is stretched, and manually operated individual means of mechanical nature for adjusting each unit of one row of bars forcibly away from the other row of bars.

4. A filter of the class described comprising a housing, two rows of bars extending transversely across said housing, the several units of one of saidrows of bars being independently and removably supported in the housing, and a filtering cloth passing over said bars in a festoon arrangement, said housing having brackets provided with knife edge lugs to receive said bars, and screw means for clamping the bars in said lugs.

Signed at -Chicago this 16th day of March, 20

BURT S. HARRISON. 

